Lamp or headlight



H. N. OT

LAMP OR HEADLIGHT 2 Shets-Sheet 1 Filed Aug. 13, 1921 WVE VTwQ? (9% wwmfi ATTORNEYS F b, 3, 1925. 1,525,196 H. N. OTT

LAMP 6R HEADLIGHT Filed Aug. 13, 1921 2 Sheets-Sheet 2 Patented Feb. 3,1925 I HARVEY N. OTT, OF BUFFALO, NEW YORK.

LAMP OB HEADLIGHT.

' Application filed August 18, 1921. Serial No. 492,094.

To all whom it may concern;

Be it known that I, HARVEY N. O'1'r, a

citizen of the United States, residing at Buffalo, in the county of Erieand State of New York, have invented'a new and useful Improvement inLamps or Headlights, of which the following is a specification.

This invention relates to improvements in lamps of the kind in which itis desired to control the direction of the rays and the field ofillumination. The invention is particularly applicable to automobileheadlights, but it is not intended to l1m1t the invention to such use.

The objectof the invention is to produce a lamp of this kind which is soconstructed that the rays emanating, from the available source of lightand reflected from a substantially parabolic reflector shall pass fromthe lamp in a beam none of whose rays areinclined upwardly from a linepassing through the axis of the reflector to cause glare in the eyes ofa pedestrian or dr1ver approaching the vehicle on which the lamp may beplaced; and also to improve the construction of lamps of this kind inother respects hereinafter specified.

It is a well-known fact that light emanating from a theoretical lightpoint placed at the focal point of a parabola and impinging upon thereflector will be reflected therefrom as a beam of parallel rays. Raysfrom a larger source so placed are reflected not only as substantially abeam of parallel rays, but

also as rays diverging from the parallel, the divergence increasing asthe points of light in the light source are placed farther from thefocal point of the.condenser,the variation from the parallel being moreor less uncontrollable.

Inasmuch as the light source must be greater than a theoretical point,and inasmuch as the greatest divergence will be in the plane of thelargest dimension of the. light source the lamp is provided with a,

eyes above or below the axis of the reflecton.

As a further precaution against upwardly extending rays a projectinghood or visor extends forwardly from the upper edge of the parabolicportionof the reflector. In

order that this may be most effective thelight source and the axis ofthe parabola beneath it should be as nearly-as possible in the planeofthis visor. This means that the parabolic portion should'be as small aspossible with a short focal length so that the light source in its focalpoint may project light to the reflector in as large an angle aspossible to increase the volume of the reflected beam. This means thelight source must be close to the apex of the condenser. In order toaccomplish this the filament is placed near the end of a small tubularbulb which is used with the base up and which is held and adjusted ashereinafter described.

In the accompanying drawings:

Fig. 1 isa longitudinal central sectional elevation of a lamp embodyingthe invention.

.Fig. 2 is a fragmentary sectional plan view thereof on line 2-2, Fig.1.

Figs. 3 and 4 are transverse sectional elevations thereof on lines 33,and 4- 4, Fig. l. i

' Fig. 5 is a bottom plan view thereof. Fig. 6-is a front elevationthereof.

The invention is illustrated in theaccompanying drawings and is-hereindescribed as applied to an automobile headlight. It is, however, notintended to limit the invention to use in connection with automobileheadlights since the same may be used for any other purpose where it isdesired to control the direction of the, rays of light.

The lamp shown in the accompanying drawings includes an outer housinghaving an upper rounded or arched wall A which is bent downwardly toform the sides of the housing and a rear wall a. The housing is providedon its upper end with an opening or slot a closed by a suitable hingedcover or the like a whereby access can be had to the interior of thehousing. A housing of any other suitable or desired construction may beemployed if desired. The, lower portion of the housing is closed bymeans of a window or glass plate B which is ar- I ranged at aninclination to the horizontal and which is suitably held in place on the6 extending inwardly from the lower edges of the housing and whichengage the lower edges of the window or plate B to hold the same inplace." If desired, the window B may be provided with an upwardlyextending portion b which, in the construction housing A, preferably bymeans of flanges shown, extends in front of .a dim light C, this lightbeing of a small candle power and arranged in a reflector c in the upperportion of the lamp. The glass window or plate in the constructionshown, is secured in place by sliding the same rearwardly intoengagement with the flanges b of the lamp housing and is held in thisposition by means of a clip 6 secured on the upper wall A of the housingand preventing the window from moving forwardly out of its operativeposition. All of these parts maybe of any other suitable construction.

The lamp or headlight includes a source of light D suitably held on theframe of the lamp, an electric incandescent lamp being used in theconstruction shown, which has its filament extending approximatelythrough the focal point of a substantially parabolic reflector or thelike E. The glass bulb or housing in which the filament of the lamp iscontained is preferably substantially tubular in construction and ofsmall diameter, the bulb being elongated as shown so that the heat fromthe filament cl can be dissipated from the upper portion of the bulb. Abulb of this construction makes it possible to use a parabolic reflectorof short focal length, which is decidedly advantageous for the reasonthat a reflector of this kind can be made of comparatively small size totake in a large angle of light from the light source and at the sametime keep the reflecting area near the forwardly projecting visor, andthus can be made to reflect a larger percentage of the light from thefilament into a parallel beam than is practicable with parabolicreflectors of 'greater focal length and of the same area.

The reflector E in the construction shown, is provided near its upperportion with an aperture 6 through which the electric lamp extends andthe front edge of the upper portion of the parabolic reflector isflattened into a substantially horizontal portion or visor F, whichextends forwardly to the front portion of the headlight. The sides ofthe flattened portion F are joined by downwardly curved side port-ions fwhich are substantially parabolic, being continuations of the paraboliccurve of the portion E of the reflector. These sides are cut off at aninclination to the horizontal, terminat ing at the plate or window B.The reflector or visor F has the effect of directing any rays of lightprojected thereon downwardly towards the road and thus prevents rays oflight from passing upwardly to produce a glare. In the constructiondescribed, the window and reflecting surfaces are so arranged relativelyto each other that all of the light rays leaving the lamp in a verticallane passing through the axis of the para ola which strike a reflectingsurface and which emanate from a theoretical light the reflector.

point placed at the focus of the parabola, are thrown out of the lampwith only one reflection. When this condition is fulfilled the reflectedrays pass out parallel to themselves and substantially horizontally-noreflected rays passing out upwardly, and a very efficient use is made ofthe light and a proper operation of the lamp without glare is ensured.By means of the construction shown, all rays of light leavin the lampemanating from the source of light D will either be reflected only onceor else will pass directly through the window without reflection, doublereflections being entirely avoided by means of this construction. Thisarrangement of the reflecting surfaces results in a very efficient useof the available light, so that practically all of the light isprojected where it is of most use, and at the same time, allobjectionable glare is avoided. By so proportioning the electric lampthat the parabolic reflector may be given a short focal length, thereflector can be made smaller than usual and can extend beyond thevertical plane of the focal point to a considerable degree, and thusreflect much light forwardly onto the road which would otherwise bewasted.

1n lamps of this kind as heretofore made, it has been found practicallyimpossible to control the reflection of the light from the parabolicreflector for the reason that the filaments of electric lamps could notbe confined to a single point such as the focal point of a parabola.Consequently. such rays as emanate from points not in the focal pointcause the reflector to project the rays of light in various directions,many of the rays passing upwardly and thus producing objectionableglare. Since electric incandes cent lamps are usually used in headlightsof this kind, this objection is difficult to overcome since the filamentof electric lamps of this kind must have considerable length and isusually arranged in the form of a coil so that rays of light emanatingfrom the filament cannot be confined to the focal point of Such rays asemanate from the filament above or below the focal point cause rays tobe reflected upwardly and downwardly, the upwardly projecting rayscausing the objectionable glare. In order to largely overcome theobjection of having some of the rays projected upwardly, the electriclamp D shown is provided with a filament arranged as nearly as possiblein a straight line and extending transversely of the lamp. The electriclamp can then be adjusted so that the filament extends substantiallytransversely of the lamp through or slightly above the focal point ofthe reflector. By means of this arrangement the rays of light emanatingfrom those parts of the filament which extend laterally beyond the focalpoint will be reflected sidewise and thus laterally increase the fieldilluminated by the lamp. Since only small portions of ment slightlyabove the focalpoint no rays the headlight.

are projected upwardly, thus the glare is eliminated and at the sametime, the field of illumination is extended laterally, which isdesirable since it enables the headlight to illuminate a wider portionof the, road. By means of the rearwardly inclined window or lens, thelower portions of the reflector may be cut away as shown and this helpsgreatly in avoiding glare since the remaining lower part of thereflector will be practically concealed by the visor.

In the particular construction of the lamp shown in the drawings, thereflector F is held in place and protected against injury by means of ashield or protector G corresponding substantially to the shap of thereflector F. This shield and reflector are preferably pressed downwardlyagainst the window or glass by means of set screws h arranged on abridge member H which is suitably secured to the housing A of the lamp.By tightening the "screws 11., the shield presses the window or glassplate B against the flanges b of the housing so as to avoid rattling andto hold the window in place in the lamp. Other means may be employed forholding the reflector in place in the lamp housing.

Means are preferably provided for adjusting the electric lamp or sourceof light 1) with reference to the reflecting surfaces of the headlightso that the source of light maybe readily placed into the correctrelation to the reflecting surfaces. In the construction shown for thispurpose, the "electric lamp D is suitably mounted on an arm of a leveror pivoted light holder I. The electric lamp may be held on the lightholder in any desired manner. In the construction shown, the electriclamp is provided at opposite sides with pins or projecting portions 2'which engage corresponding depressions in the bushing suitably held inthe pivoted light supporting member I. This construction makes itpossible to turn the electric lamp relatively to the light holder insuch a manner that the filament may be arranged to extend transverselyof The light supporting member I is pivoted at i on a second pivotedmember or adjusting lever K which is pivoted at Z: on the bridge memberH. The light supporting member I has an arm i against which a spring 2'bears and a set screw 71 extends through a hole in the arm 2' and has athreaded engagement with the pivoted adjusting lever K. The pivotedmember K is provided with a set screw in extending through a hole inthis pivoted member and engaging a threaded hole in the bridg member H.By means of this arrangement an adjustment of the set screw i will causethe filament of the electric lamp to swing about the pivot i and sincethis pivot is arranged almost vertically above the filament or source oflight, this swinging will cause the filament to move practicallylongitudinally of the headlight. An adjustment of the set screw causesthe electric lamp to swing about the pivot is and this movement of the'filament is substantially in an up and down direction because the pivotis is arrangedat a considerable distance in front of the filament.Conse-, quently, by means of the two adjusting screws the filament maybe located in the desired position in the headlight. By means of thearrangement of th spring i which is shown in the drawings, both of thetwo adjusting screws 7? audit operate against the action of the spring2", so that only one spring is required.

The electric lam may be held in place in the sleeve or bushing c" in anysuitable manner. In the construction shown, the pivoted member I hasa-downwardly extending portion Z on which an insulating member L issecured. A current conducting member Z' is mounted on the insulatingmember L and current'is conducted from this member to one of. theterminals of the lamp by means of a contact member l which is hinged onthe current conducting member Z and which is yieldingly pressed intoengagement with a terminal of th lamp by means of a springl One of theconductors m is connected to the current carrying member Z of the lampand another conductor m connects with any portion of the headlight,such, for example, as the pivoted light-supporting member I. Any othermeans for adjustably supporting the electric lamp on the headlight andfor transmitting current to the electric lamp may be employed.

The bridge member H is preferably also employed for holding the smalldim light C in place. For this purpose, a lamp carrying rod or plate Nis employed on the outer end of which the lamp socket n for the dimlight is secured. The lamp-carrying member N has a hooked portion 7:.adapted to enter into a slot 11. in the bridge member H at the end ofthe slot. The inner end of the lamp carrying member N may be held inplace in any desired manner, for example,

by means of a set screw n? adapted to enga e in a threaded hole in thebridge member and extending through a slotn in the lamp carrying memberN. The slot n has an en larged portion n through which the head of theset screw n may pass. Consequently if it is desired to remove the dimlight together with the lamp carrying member ,it is only necessary torelease the set screw a and to draw the extension member rearwardlyuntil the set screw may pass through the enlarged portion n of the slotin the carrying member, this movement of the light vcarrying member alsoreleasin the hook n from engagement with the bri ge member. Other meansfor mounting the dim light in the headlight may be provided.

The lamp or headlight described has the advantage of accuratelyprojecting the light so that the road may be Well illuminated withoutproducing any objectionable glare. Th constructionof the housing isdesirable since. it renders the parts of the lamp readily accessiblewithout necessitating the removal of the window or glass plate.

I claim as my invention 1. In a lamp, the combination of a substantiallyparabolic reflector, a visor extend-' ing forwardly from the upperportion of said reflector and having a reflecting surface formingsubstantially a continuation of said reflector, a source of lightarranged approximately in the focal point of said reflector, a housingenclosing said reflector and said visor, and extending above said visor,adjusting means for said source of light arranged in said housing abovesaid visor, and an opening in said housing above said visor forrendering said adjusting means accessible.

2. In a lamp, the combination of a substantially parabolic reflector, avisor extending forwardly from the upper portion of said reflector andhaving a reflecting surface forming substantially a continuation of saidreflector, a source of light arranged approximately in the focal pointof said reflector, a housing enclosing said reflector and said visor andextending above said visor, and a dim light arranged in said housingabove said visor.

3. In a lamp, the combination ,of a substantially parabolic reflector, avisor extending forwardly from the upper rtion of said reflector andhaving a ret dting surface forming substantially a continuation of saidreflector, a source of light arranged approximately in the focal pointof said reflector, a housing enclosing said reflector and said visor andextending above said visor, adjusting means for said source of lightarranged in said housing above said visor, a dim light arranged in saidhousing above said visor, and an opening in said housing above saidvisor for rendering said adjusting means and said dim light accessible.

4. In a headlight, an elongated casing comprising a lower compartment, alamp at the rear thereof, and an upper compartment, a relatively dimparking light at the front of the same, the lower compartment being openat the bottom and the upper compartment being closed at the top,substantially as set forth.

5. An automobile headlight comprising a casing open at the bottom, areflector at the rear of the casing, a lamp at the focus of thereflector, a relatively dim lamp above said first lamp and an opaquepartition between said dim lamp and said reflector, substantially as setforth. I

HARVEY N. OTT.

